I agree. I realize this has privacy implications, but for those of us looking for a semi-private email simply to keep the likes of Google/Yahoo/Microsoft/... from reading our email, but not trying to evade the state (not that I'm/we're not, but that's not the priority), voluntarily degrading the privacy and security a bit to vastly improve functionality is necessary. As much as I'd like a 99.9% secure email service, in reality I don't need it, and even with IMAP Tutanota and other similar services are still significantly better than the common ones, and without it they're just not usable enough to replace them. I'm comparing features of the various privacy-oriented services, and Tutanota seems promising, but without IMAP it's not usable for me.

This is important. I was set to switch from google apps till I realised there was no imap. Encrypted emails are fine, if you need it. I am mainly interested with a company that isn't logging and making money from my emails. I would gladly pay that small fee every year IF I could use imap and smtp with my own clients and apps. Just all you need to do is detect encrypted emails and just provide a web link if you want to interact with those emails. All other emails can arrive and send over normal secure imap/smtp connection. Please implement this most basic and crucial functionality.

This is a must needed feature, specially if tutanota wants to target commercial users.
Now, the apparent reason for not considering this feature is the crypto eco-system of tutanota - which mostly is based on symmetric mechanisms and not purely is PGP centric, which does have the flexibility of working with the mechanisms of IMAP(S)/POP(S). In contrast, I do agree and support the uniqueness of tutanota over PGP centric solutions that it does encrypt the subject (+ headers) of the email as well its body which others don't.
Though, the only solution which I know of being considered as a complete package (of-course with IMAP/POP) is mailfence.com, which is a 'pure' end-to-end PGP based solution.
Other solutions include scryptmail, riseup - which I believe are also working to add this feature..

In order to deliver your mail to you in the IMAP protocol, the tutao server needs to have access to the plaintext; SMTP is simply the reverse, in order to accept data the server must read in plaintext.